Softphone

X lite http://www.counterpath.com/x-lite/

SJ phone http://www.sjlabs.com/

Linphone http://www.linphone.org/

zoiper https://www.zoiper.com/

3CX https://www.3cx.com/

Blink http://promocion.vozip.com/telefonia-ip?gclid=CjwKCAiA8vPUBRAyEiwA8F1oDFDMu-j9vQ8DDXWBxpaoq02kYr5IMUtQ3i0DjANZcbi5337VFxp9LBoCnwQQAvD_BwE